An integrated circuit (IC) has a plurality of functional blocks including a central processing unit (CPU) block. A data bus of the CPU is directly connected to input/output terminals of the composite IC. The output terminal is used for outputting a read signal through a buffer to a memory.
To a certain extent, a user may be able to manipulate a maximum frequency of the integrated circuit. However, the user may not have control of a signal communicated between the IC and the memory.